GitLab

Also remove the BrowserDistribution::ShortcutType enum (since there
would only be a single value left).

BrowserDistribution depends on strings that won't be available once
enable_app_list is flipped to 0 on Windows. Since these constants are
generated by create_string_rc.py (which is hard to #ifdef), and used on
the single `DO_INSTALLER_STRING_MAPPING` line of
chrome_browser_main_win.cc, it's hard to prepare for the flip without
this first step.

Remove accesses to those strings by nerfing the app list install flow on
Windows and removing the icon and relaunch customizations.

For now, this just makes the app launcher window show in the taskbar
with a Chrome icon, and no window title. A follow-up in m52 will cause
attempts to show the app launcher window instead just open a browser
window at chrome://apps.

BUG=600915

Review-Url: https://codereview.chromium.org/1926403002
Cr-Commit-Position: refs/heads/master@{#393415}